Cleansing device for rock drills



July 26, 1938. E. F.' TERRY i 2,12

CLEANSING DEVICE f'ok ROCK DRILLS 1 Filed April 10. 1936 INVENTOR H as ATTORNEY.

Patented July 26, 1938 UNITED STATES PATENT OFFICE CLEANSING DEVICE FOR ROCK DRILLS Application April 10,

1 Claim.

This invention relates to cleansing devices, but more particularly to a device for supplying cleansing liquid directly to the working implement of a fluid actuated rock drill.

One object of the invention is to assure an adequate supply of cleansing liquid to a drill hole to flush the cuttings from the Working surface.

Another object is to prevent the passage of pressure fluid from the rock drill into the drill hole.

Other objects will be in part obvious and in part pointed out hereinafter.

In the accompanying drawing forming a part of this specification and in which similar reference numerals refer to similar parts,

Figure 1 is a sectional elevation of so much of a rock drill as will serve to illustrate the invention and a practical application thereof, and

Figure 2 is a transverse view taken through 20 Figure 1 on the line 2-2.

Referring more particularly to the drawing, the rock drill embodying the invention and designated in its entirety by 20, comprises a cylinder 2!, a front head 22 and a hollow spacer 23 interposed between the cylinder and the front head. These elements constitute casing parts of the rock drill and may be held securely in the correct assembled relationship with respect to each other by side rods 24 disposed on opposite sides 30 of the rock drill.

The spacer 23 has an annular extension 25 that extends into the front head 22 to centralize these elements with respect to each other and is centralized with respect to the cylinder by a front cylinder washer 25 extending into the contiguous ends of the cylinder and the spacer. A flange 2! on the periphery of the front cylinder washer acts as a seat for the ends of the cylinder and the spacer.

The cylinder 29 contains a hammer piston 28 for actuating a working implement 29 extending into the front head 22. The piston 28 has a stem 30 which is guided by the front cylinder washer 26 and has longitudinally extending flutes 3| to receive and interlock slidably with ribs 32 in a sleeve 33 rotatable in the spacer 23.

In the rear end of the cylinder 2| is arranged rotation mechanism of well known type comgages the piston 28. The rifle bar has a head 35 and pawls 36 in the head 35 cooperate with the teeth 31 of a ratchet ring 38 for holding the rifle bar against rotary movement and thus cause 55 the piston 28 to describe a partial revolution durprising a rifle bar 34 which interlockingly en 1936, Serial No. 73,674

ing its rearward stroke for rotating the working implement. 1

In accordance with the practice of the invention the chuck mechanism guiding the Working implement 29 comprises a sleeve 39 having a bore 40 to receive the shank of the working implement. In the front end of the sleeve 39 are threads 4| to engage threads 42 on the working implement for securing the two securely together. The rearward portion of the bore 49 is in body engagement with the adjacent portion of the working implement and, as a preferred form of construction, the sleeve 39 is provided with an enlarged recess 43 having threads 44 for engagement with threads 45 of a plug 46. The plug preferably seats upon the bottom of the recess 43 and has a beveled surface 41 that cooperates with a corresponding surface 48 on the end of I the working implement 29 to effect a seal at that point.

The plug 46 carries a stem 49 which extends into the sleeve 33 and has flutes 5D to receive the ribs 32 on the sleeve 33. The stem 49 is imperforate and projects into the path of the stem 30 to receive the blows of the piston and transmit them to the working implement 29.

In order that pressure fluid flowing along the stem 30 of the piston toward the front end of the drill may be prevented from entering the chuck mechanism the sleeve 33 is provided with an aperture 5|, preferably adjacent the free end of the stem 49. The aperture 5| opens into an annular groove 52 in the periphery of the sleeve 33, and a vent 53 in the spacer 23 affords communication between the groove 52 and the atmosphere.

Within the front head 22, and encircling the sleeve 39, is an annular chamber 54 into which cleansing fluid is constantly delivered by a conduit 55 connected to the front head. The ends of the chamber 54 are sealed by packing members 56 which are pressed into sealing engagement with the periphery of the sleeve 39 by a spring 51 interposed between the packing members.

In the periphery of the sleeve 39 is an annular groove 58 which, when the chuck mechanism and the working implement are in their rearmost limiting positions to receive the blows of the hammer piston 28, registers with the chamber 54, and from the annular groove 58 lead passages 59 which open into the front end of the recess 43. The block 49 is likewise provided with a series of passages 60 and. an axial passage 6| communicating with the passages 60 and with a passage 62 in the working implement 29.

Preferably, the annular groove 58 is so positioned that it opens into the chamber 54 near the front end of said chamber when the chuck mechanism lies in its rearmost limiting position. The chuck mechanism is slidable within the front head and capable of a considerable degree of longitudinal movement therein. Thus, when the rock drill is inoperative, the chuck mechanism may be moved forwardly to move the groove 58 out of communication with the chamber 54 and thereby cut off communication between the passage 62 in the working implement and the source of cleansing liquid supply.

During the normal operation of the drill and when the working implement is pressed against the Work the chuck mechanism lies in its rearmost limiting position so that the annular groove 58 will be in full communication with the chamber 54. In this position of the parts cleansing fluid flows from the chamber 54 through the groove 58 and the passages 59, 60, BI and 62 into the hole being drilled and flushes the cuttings to the surface of the ground. Cleansing fluid continues to flow through these channels as long as the chuck mechanism remains retracted so that the stem 49 is in position to receive the blows of the hammer piston 28. In the event, however, that the drilling operation is interrupted, as when changing working implements, the chuck mechanismis drawn forwardly in the front head, preferably to a position in which the annular groove 58 lies forwardly of the front packing member 56. In this way the groove 58 will be moved out of communication with the chamber 54 and no cleansing fluid will, therefore, flow to the drill hole. Whenever it is again desired to resume drilling the percussive element of the rock drill is set in operation and the working implement pressed against the work to move the chuck mechanism rearwardly in the front head. The passages in the working implement and the chuck mechanism will then again be communicated with the source of liquid supply and without necessitating the manipulation of valve means exteriorly of the rock drill, as is customary.

I claim:

In a rock drill, the combination of a casing and a working implement extending thereinto and having a passage for cleansing fluid, a hammer piston for actuating the working implement, a hollow rotary member in the casing having internal ribs in engagement with the piston, a

sleeve slidable in the casing and being threadedly connected to the working implement, means threaded into the sleeve and seating against the end of the working implement for transmitting the blows of the hammer piston to the working implement, an imperforate stem on said means having flutes to receive the ribs on the rotary member, and a supply passage in the sleeve and the said means for conveying cleansing fluid to the passage in the working implement.

EDWARD F. TERRY. 

